Construction Of Sequences Research Articles

Protecting-group-free mechanosynthesis of amides from hydroxycarboxylic acids: application to the synthesis of imatinib

The mechanochemical protecting-group-free amidation of hydroxycarboxylic acids is presented. The transformation is applied to the synthesis of imatinib via a two-fold C–N bond construction sequence that bypasses a chlorinated genotoxic intermediate.

A multifunctional synergy development evaluation model of the impact of the cascade reservoir construction sequence on basins

Considering the mass reservoirs construction, it is important to study the cascade reservoir construction sequence, which directly affects the water and sediment resource allocation, ecological environment restoration, and socioeconomic development of the basin. Thus, we constructed an evaluation index system by comprehensively considering the basin water and sediment discharge index, basin ecological and environmental maintenance index, and basin social and economic development index. The evaluation model was established to assess the impact of the cascade reservoir construction sequence on basin multifunctional synergy development index. The model was applied to evaluate the cascade reservoir construction sequence in the Yangtze and Yellow River Basin of China. The results revealed that: (1) The basin water and sediment discharge index, basin social and economic development index, and basin multifunctional synergy development index benefits gradually increased, the basin ecological and environmental maintenance index benefits progressively decreased in the Yangtze and Yellow River Basin. (2) The basin water and sediment discharge index, and basin ecological and environmental maintenance index of the planned cascade reservoir construction sequence ranked top in the Yellow River Basin; the basin water and sediment discharge index, and basin social and economic development index of the planned cascade reservoir construction sequence ranked top in the Yangtze River Basin. (3) The cascade reservoir construction sequence focused more on basin social and economic development index benefits when the level of national economic development was low, and more on basin water and sediment discharge index benefits when it was high. (4) Reservoir capacity and installed capacity were the main factors influencing the cascade reservoir construction sequence in the Yangtze and Yellow River Basin, respectively. These findings provide useful information regarding the cascade reservoir construction sequence.

Bridge assessment based on deflection as a measure of damage using Machine Learning-enhanced pattern identification

Bridges worldwide are failing at increasing rates as they heavily suffer from deterioration, leading to transport infrastructure system disruptions and millions of financial losses. For instance, the failure of the Polcevera bridge alone, costed €359 million in the immediate wake, while the estimated annual losses for the Italian economy are close to one billion euros. Despite the recent technological advancements in the field of structural health monitoring, involving digital measurements and remote data collection, bridge failures still occur. The reasons behind those failures are mainly due to the pertinent damages being not easily detectable and the scarcity of the available design drawings, especially for old bridges. Furthermore, the construction sequence for the asset of interest or the level of prestressing are often not known in detail, hence the as-built condition and the actual bridge properties are highly uncertain. This is a capability gap that can only be filled with meaningful data collection and application of advanced technologies in aid of decision-making. The paper aims to extend an existing methodology that was proposed before by Kazantzi et al. (2024a, 2024b) for identifying the damage state of bridges. The aforementioned methodology was initially showcased for balanced cantilever concrete bridges only. To further advance the methodology, application to other concrete bridge typologies, including beam and slab bridges, cast-in situ slabs, continuous box-girders, and arch bridges, is herein proposed. Additionally, the paper suggests validating the machine learning kNN (k-Nearest Neighbor) methodology utilizing Finite Element (FE) model updating. This process involves adjusting numerical model parameters to better match actual structural behavior, enhancing the methodology’s reliability and effectiveness for identifying damage states in concrete bridges of different types and scenarios.

Reinforced Soil Wall Construction with High Stiffness Geocomposite Reinforcement and Betoflor Segmental Block, Pengerang, Johor Darul Ta’zim

Pengerang is a municipality in Kota Tinggi district in Johor at the southern tip of the Peninsular Malaysia. It is home for the mega oil and gas hub Pengerang Integrated Petroleum Complex (PIPC) in Southern Johor state, which is one of the region’s largest hubs for oil and gas, petrochemical industries, oil storage and trading activities. The area is experiencing significant development, both residential and commercial in nature. In this development plan, the retaining wall system plays a crucial role in providing a larger development area, enhancing the aesthetic view, and achieving a higher elevation platform. The focus of this paper is on an internally stabilized reinforced soil wall system which involves reinforcing the soil with high stiffness geocomposite reinforcement and utilizing modular segmental blocks as facing elements. This combination creates a 1 vertical: 0.14 horizontal gradient (82°) wall that is implemented for a mixed development at Pengerang. The single-tier reinforced soil wall reaches a height of 13 m. In addition, the maximum 14 m high wall was designed as a two-tier wall and the maximum 19 m high wall was designed as a three-tier wall. The design of the reinforced soil wall includes the evaluation of various potential internal and external failure modes. This paper also discusses the construction sequences employed for the reinforced soil wall. Ultimately, the combination of the high stiffness geocomposite reinforcement with modular segmental blocks has proven successful, resulting in a constructed wall that satisfied the client requirements

A novel AluYb8 insertion-associated non-coding RNA, lncMUTYH, impairs mitochondrial function and dampens the M2-like polarization of macrophages

An inverted AluYb8 insertion in the MUTYH intron 15 (AluYb8MUTYH variant) has been reported to be associated with reduced MUTYH1 expression and mitochondrial dysfunction with age. However, the underlying mechanism remains unknown. In this study, we identified a novel transcript associated with the AluYb8MUTYH variant, which revealed that this transcript is about 780 nucleotides in length with a poly-A tail, lacks protein-coding potential, referred to as lncMUTYH. The results from the reporter gene system confirmed that the lncMUTYH down-regulates MUTYH1 expression at the translational level. Site-directed mutagenesis on the 5′-terminal exon sequences of α-MUTYH and lncMUTYH constructs revealed that lncMUTYH can act as a trans-regulator that depends on the partial base pairing between its exonized AluYb8 sequence and the 5′UTR of α-MUTYH to impede MUTYH 1 expression. Furthermore, we have demonstrated a correlation between decreased mitochondrion-localized MUTYH1 caused by lncMUTYH and lowered levels of mitochondrial biological function indicators, such as mtDNA content, mitochondrial regulatory gene expression, oxygen consumption rate, ATP product, and mitochondrial respiratory capacity. Notably, we found that lncMUTYH inhibited the M2-like polarization of macrophages, and CD68/CD206-positive cell fractions were significantly lower in lncMUTYH ectopically expressing cells. The results confirmed that the AluYb8MUTYH-associated lncMUTYH, derived from an AluYb8 insertion mutation, acts as a trans-regulatory factor that inhibits the MUTYH1 protein expression, leading to a progressive mitochondrial dysfunction that may disrupt macrophage differentiation. In summary, lncMUTYH can contribute to AluYb8MUTYH-associated mitochondrial dysfunction with age and hamper the macrophage polarization process, potentially increasing the risk of developing age-related diseases.

Comparison of the bearing capacities of a small-diameter bored pile obtained from the results of field tests and numerical modeling

Abstract. The paper compares the results of modeling static soil tests with a small-diameter drill pile with the data obtained from field tests. The calculations were performed by numerical modeling using the PC software "Plaxis", which is based on the finite element method. This problem was solved in a flat (2D) formulation for an axisymmetric model, which makes it possible to analyze the stress-strain state (SSS) and the interaction of elements of the pile-soil environment system.
 Separate computational models were created for two types of piles made using different technologies: a bored- CFA pile and a drilled pile with partial soil displacement. In order to take into account the preload history in order to maximize the models' approximation to real conditions, the calculations were performed in 4 stages in accordance with the construction sequence: Stage 1 - initial stage (determination of the initial stresses in the soil massif in the natural state), Stage 2 - excavation to the design mark of the pit bottom, Stage 3 - testing of the soils with a pile by static load. Stage 4 - pile unloading. Based on the results of the calculations, the SSS and the interaction of the elements of the "pile-soil environment" system have been analyzed and compared the settlement graphs obtained from the results of the calculations with the data of field tests.
 It is shown that the use of a plane axisymmetric FEM is a sufficiently effective approach for assessing the stress-strain state and understanding the interaction of elements of the pile-soil system, as well as predicting the bearing capacity of piles for further design of the pile foundation before obtaining the results of field tests. In addition, the labor intensity and time consumption of this approach are relatively low compared to other alternative methods.
 With appropriate experience in using this approach in different soil conditions with appropriate comparison with field test data, it can be applied in the feasibility study and final decisions on the choice of a particular type of foundation.

Assessment of the impact of a high-rise building on the stress-strain state of the foundation and structures of existing buildings in dense development

One of the most progressive problems of modern urban planning is the gradual decrease in areas suitable for construction, especially within the historical districts of cities. This prompts developers to increasingly develop sites in difficult engineering and geological conditions, which are often located within dense buildings.
 Today, the construction of multifunctional residential complexes combines the construction of high-rise residential sections and commercial real estate buildings with multi-level parking lots, which are often located in close proximity to each other. Often, the sequence of construction of these buildings is stretched over years or even decades, for example, due to an unfavorable economic climate or the instability of the political situation in the country, which leads to the commissioning of only certain stages of construction. The subsequent resumption of construction work requires taking into account the mutual impact of new construction and observations of previously constructed buildings during the construction of new structures.
 The execution of deep pits at the stage of laying the foundations of new buildings, as well as the substantial weight of high-rise buildings, causes a change in the stress-strain state of the adjacent soil massif, so designers face the task of determining the impact of such construction on the adjacent buildings.
 This article presents the results of a study of the change in the stress-strain state of load-bearing structures and foundations an existing building, taking into account the mutual impact of an adjacent high-rise section of a residential complex.
 The calculations were performed in two independent software systems Plaxis 3D and LIRA-FEM, in the spatial formulation of tasks, for a comprehensive assessment of the SSS of the system "soil base-foundation-superstructure".
 The zone of impact of new construction on the adjacent buildings, the values and character of additional displacements of foundations of adjacent structures are determined. The regularities of changes in the calculated forces in piles are shown, which indicate a decrease in axial forces in piles up to two times at the interface with the foundations of the new building and an increase in the load on the piles of the central zone by up to 17%. The obtained results show a tendency to redistribute stresses in the foundation slab from the bearing zones to the span zones, as well as in the bearing vertical structures of the lower floor of the existing building.

Research on the Proportion and Strength of Joint Filler Materials for External Wall Tiles

Tile is the main exterior material of reinforced concrete building in Taiwan. However, the tiles are peeled off due to the deterioration of the building or the force of the earthquake recently. The construction sequence of exterior wall tiles includes cement mortar, waterproof layer, adhesive layer, paste tile and caulk. Most of tiles peel off from the adhesive layer so there are many studies focusing on the construction of adhesive layers. If the adhesive is not applied during construction or deteriorates over the years, it will lose its adhesion, and the caulk plays an important role in fixing the tile to the wall. Therefore, it is necessary to study the joint filling of exterior wall tiles. In this study, the exterior wall construction problems are sorted out, workers often ignore the proper water-cement ratio due to rush work in the construction site. The purpose of this study is to verify the effect of the water-cement ratio of the tile joint filler on the strength by pull-off and shear experiments. Set the water-cement ratio of joint filler to 1:4, 1:2, 1:1.3, 1:1, and quantitatively use in the same area. The results showed that the caulk with a water-cement ratio of 1:4 showed the best pull-off strength, which is 4.5 times that of 1:2. The increase in water volume at the construction site due to rush would lead to a significant decrease in strength. We look forward to providing a reference for on-site construction in this study.

Multi-loop Nesting Algorithm and Response Analysis of Cable Forces of Long Span Cantilever Cast Arch Bridges during Construction

The existing calculation process of the cantilever cast arch-cable force has a poor fit with the actual process, leading to the lack of good parameter corrections. To improve the overall control quality of the linearity and stress of the arch ring, there is an urgent need for a solution method with higher flexibility and better practicability. Combined with the existing research results, this study proposes a multi-loop nesting algorithm. The algorithm decomposes the whole construction process into individual subsystem control modules, and sets the control indexes of stress and displacement in individual control modules. Subsequently, the analysis and calculation of other modules are completed according to the construction sequence until structure closure. Finally, we determine whether the overall construction control indexes meet the requirements. According to the findings, the results obtained by this algorithm meet the design requirements, and its applicability is verified. Compared with other algorithms, the algorithm is more effective in controlling the stress and deformation of the arch ring during the construction process. This algorithm solves the dispersion between structural systems in previous calculations and has more flexible parameter and control index settings. Additionally, the calculation control idea of this algorithm can be further extended to the construction control of the “cable-beam” cantilever structure.

The effects of excavating twin tunnels during cyclic loading on the progressive settlement of existing footing

Tunnels may be constructed in a pair undercrossing existing geotechnical structures exposed to cyclic loading. Such construction changes the stress state in the ground in different ways regarding the tunnelling sequence and would lead to large settlement or even failure to those structures under cyclic loading. Large physical model tests were carried out to examine the impact of excavating twin tunnels during cyclic loading on the progressive settlement of footings. The vertical soil stress, footing settlement and ground deformation were analysed regarding different construction sequences and spacings between twin tunnels. The results indicate that previous cyclic loading history affects the alteration of soil stress caused by tunnelling activity. Compared with excavating twin tunnels successively, excavating the tunnels in sequence leads to greater settlement caused by the subsequent cyclic loading. The change in the relative density of soil is invalid to explain the enlargement of the settlement. Finite element analysis was performed to investigate the mechanism of the effects of excavating twin tunnels during cyclic loading on the footing settlement. It was found that the increase of footing settlement in the subsequent cyclic loading and the greater settlement in the sequential tunnelling case are attributed to the greater stress ratio (q/p) in the ground.

Deformation Law of Tunnels Using Double-Sidewall Guide Pit Method under Different Excavation Sequences

The double-sidewall guide pit method finds extensive application in the construction of large cross-section tunnels in soft rock strata due to its minimal disruption to the surrounding rock, thereby enhancing tunnel stability. To investigate the loading and deformation patterns of the surrounding rock and tunnel support using the double-sidewall guide pit method, this study compares the impacts of various construction sequences on surface settlement, surrounding rock stress, and lining stress using indoor model tests. The experimental results show that after excavating the upper guide hole on one side, the excavation of the lower guide hole on the same side is carried out. The upper and lower support structures form a closed loop, and the structure can better constrain the surrounding rock and control the deformation of the surrounding rock, whereas the lower structure can share the stresses suffered by the upper structure. Therefore, compared with the upper and lower excavation methods, the surface settlement caused by the left and right excavation methods is smaller, the disturbance to the surrounding rock is smaller, and the supporting structure is more evenly and stably stressed in the excavation process.

3D FE modeling of a complex multi-stage foundation underpinning for a high-rise building

ABSTRACT The piled foundation of an existing high-rise building in Cairo was assessed as inadequate. The building foundation consists of 370 piles arranged below the columns and walls. The building was constructed in 1977, and up to the start of this investigation in 2014, it was just a concrete skeleton without finishing. The existing foundation was subjected to underpinning in 1985 using micropiles to support new lateral load-resisting elements proposed by the project structural consultant. According to the new Egyptian codes of practice, underpinned foundations are still considered inadequate and it was proposed to add additional micropiles with a raft connecting the different pile groups. This paper presents the 3D FE modeling for this complex multi-stage foundation underpinning considering the construction sequence and the different interactions between the original piles, existing and proposed groups of micropiles, supporting soil and the capping raft. The load transferred by direct contact between the raft and the soil is also investigated. Available detailed geotechnical investigation and evaluation of the available micropiles loading tests were used to estimate the parameters of soil and pile−soil interface. The advanced 3D FE model is used to ensure that the proposed number of additional micropiles satisfies the required safety and stability. The outcome of the analysis proved to conservatively satisfy safety requirements. The raft transferred a considerable part of the total load directly to the soil, hence increasing the capacity of the combined piled raft foundation system.

Investigation on heat transfer mechanism of asphalt pavement in winter transportation: An experimental and numerical study

The asphalt pavement is prone to temperature segregation. Most current studies focus on the temperature variation of hot-mix asphalt (HMA) during the paving stage in normal conditions. However, there is a lack of investigation on the performance of HMA during transportation process in winter. Insulation layers are necessary to prevent the change of HMA property, being equipped on the transportation truck. Field tests are performed on a highway to estimate the feasibility of insulation materials by monitoring the temperature variation of HMA throughout the transportation process. A Multiphysics finite element model is developed in COMSOL. The sensitivity analysis is conducted in terms of the properties of HMA. The insulation layer is effective in impeding heat transfer and keep the temperature of HMA. This improvement is more intense at larger depths. The environmental condition is less influential than the HMA properties. Recommendations are provided to moderate driving routes and locations of the mixing station by determining the worst cooling rate. This study aims to reveal the performance of insulation material and HMA in winter constructions for a typical highway. A theoretical basis is provided to optimize the construction sequences based on the investigation of the heat transfer mechanism.

Quantification of differential axial shortening in reinforced concrete and concrete-filled steel-tube-based building structures

ABSTRACT This paper compares the axial shortening behaviors of reinforced concrete (RC) and concrete-filled tube (CFT) columns in high-rise building structures and proposes a relationship between the differential axial shortening and the dead load portion. This relationship can be used to determine the initial column sections in the preliminary design of building structures. Factors that can influence the differential axial shortening in columns were considered, and numerical analyses were conducted to compare the relative effectiveness of CFT columns. The time-dependent deformation of concrete was found to be the most significant influencing factor when compared with the flattening process of each floor level and construction sequence analysis. However, parametric studies demonstrate that axial shortening behavior can be ignored in buildings of fewer than 20 floors, and that it has a negligible effect even in taller buildings. Notably, the differential axial shortening effect can be excluded in the preliminary design stage when the dead load portion is less than 30% of the ultimate axial resistance. In the absence of design standards recommendations for reference values to minimize serviceability or damage problems in building structures, the proposed relation between the differential axial shortening and the dead load portion can be effectively used to determine initial column sections in the preliminary design of building structures.

Transformer language model for mapping construction schedule activities to uniformat categories

Creating consistency among project schedule data, BIM, and payment applications requires activities in a construction schedule to be mapped with the most relevant ASTM Uniformat classifications. To do so, we introduce UniformatBridge, a new transformer-based natural language processing model, that automatically labels activities in a project schedule with Uniformat classification. Our model introduces construction sequencing tokens that capture logistically-constrained predecessor and successor activities into BERT architecture. We also introduce a dataset of real-world construction project schedules with their ground-truth Uniformat classifications for validation. Experimental results using this dataset achieve F1-scores of 0.93 and 0.87 when matching unstructured schedule data to Uniformat Level 2 and 3 classifications, respectively. We share how our method unlocks development of new techniques to (1) automatically create 4D BIM, and (2) computer-vision progress monitoring to tie semantic segmentation of reality capture data based on Uniformat classes against schedule or payment application data structures, with/without BIM.

The b-symbol weight hierarchy of the Kasami codes

The symbol-pair read channel was first proposed by Cassuto and Blaum. Later, Yaakobi et al. generalized it to the b-symbol read channel. It is motivated by the limitations of the reading process in high density data storage systems. One main task in b-symbol coding theory is to determine the b-symbol weight hierarchy of codes. In this paper, we study the b-symbol weight hierarchy of the Kasami codes, which are well known for their applications to construct sequences with optimal correlation magnitudes. The complete symbol-pair weight distribution of the Kasami codes is determined.

Significance of construction sequence and the initial behaviour in concrete-faced rockfill dams

ABSTRACT Finite Element Model simulations are widely used to validate experimental and field observations. Out of these, modelling and comparing the stability of dams under various loading conditions presents significant challenges for researchers and practitioners, none more than the concrete-faced rockfill dams that are present in Australia (e.g. Cethana dam) and around the globe. A review shows that the construction sequence of such dams has not been incorporated in the initial configuration of concrete-faced rockfill dams. In this research, static analysis has been conducted for 2D and 3D finite element models of the Kotmale concrete-faced rockfill dam (CFRD) with and without the construction stage. Both 2D and 3D analysis of the case study dam using MIDAS FEA NX software and static analysis have been conducted. A linear elastic material model and a nonlinear material model (Duncan and Chang EB Model) were used to model the rockfill material. The resulting deformations were compared with the in-situ measurements to identify the accuracy of the developed cases. Results show that construction stage inclusion and the nonlinear material model agree well with the in-situ measurements, warranting the need for such advancements in Finite Element Analysis. Such an inclusion can model future settlement behaviour reasonably well, which can lead to the development of appropriate management measures.

Rehabilitating El Pozito, Northern Belize: a Classic Maya town and its socioeconomic history as reflected in ceramics and architecture

AbstractThis article revisits a long-neglected site in Northern Belize, the Classic Maya settlement of El Pozito, located in the Orange Walk District. Investigations led by Mary Neivens and Dennis Puleston explored the site between 1974 and 1976, documenting its architecture and recovering a substantial quantity of artifacts. Afterward, events conspired to bring these investigations to a close, leaving the site in a half-century scholarly limbo. The research here seeks to rectify this. Combining extant field notes with sporadic publications and recently conducted ceramic analysis, the authors reconstructed El Pozito's sequence of construction, occupation, and usage over 20 centuries. This new research revealed a settlement of surprising complexity, combining aspects of urban functionality amid a landscape of rural complexity. This article argues that the best way to understand such complexity is through the conceptual lens of a “town.” Neither a city nor a dispersed rural settlement, El Pozito functioned as a critical node that connected local, agrarian Maya with each other as well as the whole of the Classic Maya world. In this way, the research here seeks to rehabilitate this site, rescue it from its scholarly limbo, and restore its place in understanding the complex pre-Columbian landscapes of Northern Belize.

Spatial Feature Analysis of the Beijing Forbidden City and the Shenyang Imperial Palace Based on Space Syntax

As two of the most complete existing examples of royal architecture and cultural World Heritage Sites in China, the Beijing Forbidden City and the Shenyang Imperial Palace are distinctive in terms of their spatial organization. This study used the relational diagram method of space syntax theory to quantitatively analyze the spaces of these two palaces. Furthermore, the characteristics of these spaces were explored by comparing the integration and depth value of each palace space, as well as the differences in architectural culture between the different times and nationalities that they reflect. The results show that in the Forbidden City, office space had the lowest degree of spatial enclosure (depth value), while living space had the highest spatial enclosure. Moreover, there was little difference in accessibility (integration value) among office space, living space, and recreation space. In the Shenyang Imperial Palace, the accessibility of office space, living space, and recreation space showed a decreasing trend, while their spatial enclosure showed an increasing trend. The depth values of office space, living space, and recreation space were higher in the Beijing Forbidden City than in the Shenyang Imperial Palace by 245%, 109%, and 35%, respectively. The integration value of office space was 22.2% higher in the Shenyang Imperial Palace than in the Forbidden City, while the integration values of living space and recreation space were higher in the Forbidden City than in the Shenyang Imperial Palace by 13.9% and 49.2%, respectively. The degree of enclosure of the recreation spaces in both palaces was very strong, indicating that the royal family paid attention to privacy during their leisure activities. In the process of use, the functional conversion of different palaces in the Forbidden City significantly improved the accessibility of both the emperor’s living space and the minister’s office space and simultaneously strengthened the connection between these two spaces. Factors in the construction sequence led to the unreasonable accessibility of recreation space in the Shenyang Imperial Palace.

Study on the effect of excavation sequence of three-hole shield tunnel on surface settlement and segment deformation

In order to study the influence of excavation sequence of three-hole parallel shield tunnel on surface settlement and segment convergence, an improved “three-stage analysis method” was proposed to calculate the surface settlement of three-hole parallel shield tunnel. Based on Peck's existing theory, this method deduced the ground settlement formula under the three-hole parallel condition, and can calculate the ground settlement more accurately. Based on the engineering background of a shield tunnel section in Jiangsu Province, a three-dimensional model of a three-hole parallel shield tunnel was established by using Flac3d software, and the three-hole parallel shield tunnel was simulated under four working conditions: right–center–left, right–left–center, right–left–right and right–center (reverse)–left. This paper analyzed the influence of tunnel excavation sequence on surface settlement, soil displacement and deformation of tunnel segments. The construction sequence was optimized based on the above influencing factors. It was found that Case 4, S-type sequential excavation, produced the least ground settlement. The surface settlement value caused by S-type excavation sequence was only 11.41 mm, and the convergence value of the segments generated by S-type excavation sequence was relatively small. Considering the economic factors such as construction efficiency and benefit, the S-shaped excavation sequence was better. The new calculation method of tunnel surface settlement and the optimal sequence of tunnel construction proposed in this paper can provide reference for actual construction.